Processing of semiconductor devices typically involves many steps in which layers of material are formed over a substrate and subsequently patterned into a desired feature or structure. Typical features or structures include conductive lines and contact openings. Each time a patterning or etching step is conducted, certain risks arise which can jeopardize the integrity of a wafer being processed. For example, a mask misalignment error can cause a subsequent etch to undesirably etch into wafer or substrate structure which can cause catastrophic failure. Accordingly, a need exists to reduce the number of processing steps utilized in the formation of integrated circuitry.
This invention arose out of concerns associated with reducing the number of processing steps needed in the formation of integrated circuitry. This invention also arose out of concerns associated with improving the manner in which integrated circuitry memory devices, and in particular DRAM devices are fabricated.